Clinical Trial Suspicion Among US Adults as a Barrier to Research Participation in the United States

OBJECTIVE: Suspicion of clinical trials may represent an upstream attitudinal barrier to engagement with clinical research. We estimated the prevalence and correlates of clinical trial suspicion among US adults. METHODS: Cross-sectional analysis of 6905 US adults from the 2024 Health Information National Trends Survey (HINTS 7). The primary outcome was agreement that "people should be suspicious of clinical trials." Survey-weighted logistic regression with multiple imputation estimated average marginal effects and adjusted odds ratios across sociodemographic and health factors, institutional trust, political orientation, and cancer-related beliefs. RESULTS: ∼27.9% of US adults (95% CI: 26.1%-29.7%) expressed suspicion of clinical trials. In fully adjusted models, non-Hispanic Black adults had the highest probability of suspicion (AME, +15.5 pp; P<0.001), followed by non-Hispanic Asian (AME, +13.4 pp; P=0.019) and Hispanic (AME, +7.1 pp; P=0.006) adults, compared with non-Hispanic White adults. High health care system trust was inversely associated with suspicion (AME, -8.8 pp; P<0.001). Conservative (AME, +8.2 pp; P=0.001) and moderate (AME, +6.7 pp; P=0.004) political orientations had higher probabilities of suspicion compared with liberal political orientation. Agreeing that there are too many recommendations about preventing cancer was also associated with suspicion (AME, +5.9 pp; P=0.005). CONCLUSION: Over a quarter of US adults reported suspicion of clinical trials, with variation across sociodemographic and attitudinal factors. Clinical trial suspicion may contribute to systematic differences in trial participation and access to clinical innovation.